Originally Posted by
pyffer3
I use a Brother CS6000i and this started this week! I have cleaned it, changed the needle and bobbin and retreaded. I don't mess with the tension. This is on the bottom and happens at the beginning of stitching. It was bird nesting too but that must have straightened out with all the work I did
I suspect that there's something blocking the top thread path. Could there be a bit of thread stuck in the tension mechanism?